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Sci Total Environ ; 803: 149747, 2022 Jan 10.
Article En | MEDLINE | ID: mdl-34487895

This study estimates exposure and inhaled dose to air pollutants of children residing in a tropical coastal-urban area in Southeast Brazil. For that, twenty-one children filled their time-activities diaries and wore the passive samplers to monitor NO2. The personal exposure was also estimated using data provided by the combination of WRF-Urban/GEOS-Chem/CMAQ models, and the nearby monitoring station. Indoor/outdoor ratios were used to consider the amount of time spent indoors by children in homes and schools. The model's performance was assessed by comparing the modelled data with concentrations measured by urban monitoring stations. A sensitivity analyses was also performed to evaluate the impact of the model's height on the air pollutant concentrations. The results showed that the mean children's personal exposure to NO2 predicted by the model (22.3 µg/m3) was nearly twice to those measured by the passive samplers (12.3 µg/m3). In contrast, the nearest urban monitoring station did not represent the personal exposure to NO2 (9.3 µg/m3), suggesting a bias in the quantification of previous epidemiological studies. The building effect parameterisation (BEP) together with the lowering of the model height enhanced the air pollutant concentrations and the exposure of children to air pollutants. With the use of the CMAQ model, exposure to O3, PM10, PM2.5, and PM1 was also estimated and revealed that the daily children's personal exposure was 13.4, 38.9, 32.9, and 9.6 µg/m3, respectively. Meanwhile, the potential inhalation daily dose was 570-667 µg for PM2.5, 684-789 µg for PM10, and 163-194 µg for PM1, showing to be favourable to cause adverse health effects. The exposure of children to air pollutants estimated by the numerical model in this work was comparable to other studies found in the literature, showing one of the advantages of using the modelling approach since some air pollutants are poorly spatially represented and/or are not routinely monitored by environmental agencies in many regions.

Air Pollutants , Air Pollution, Indoor , Air Pollution , Air Pollutants/analysis , Air Pollution/analysis , Air Pollution, Indoor/analysis , Brazil , Child , Environmental Exposure/analysis , Environmental Monitoring , Humans , Particulate Matter/analysis , Schools
Sci Total Environ ; 803: 150043, 2022 Jan 10.
Article En | MEDLINE | ID: mdl-34525697

Soil is a major reservoir and a secondary source of semi-volatile organic chemicals, while studies on the pollution status of halogenated flame retardants (HFRs) in agricultural soils are limited. In this study, a total of twenty-five chemicals including novel brominated flame retardants (NBFRs), polybrominated diphenyl ethers (PBDEs), and dechlorane plus (DPs) was analyzed in the agricultural soils across China to investigate the occurrence, spatial distribution, potential sources, influencing factors and their associated human health risks. The results showed that BDE-209 (125-130,183 pg/g, dry weight, d.w.) was the most abundant flame retardant of PBDEs, followed by decabromodiphenyl ethane (DBDPE) (9.27-22,864 pg/g, d.w.). Meanwhile, the DPs (anti-DP plus syn-DP) were in the range of ND-1229 pg/g (d.w.), and the range of fanti values (the concentration of anti-DP divided by the sum of the concentrations of two isomers) in this study greatly matched those of commercial products, suggesting the effect of proximity to the source region. The higher levels of HFRs were found in Eastern and Southern regions of China. Spatial distribution implied that e-waste recycling activities and plastic processing have shown more importance in releasing legacy flame retardants (FRs) into the environment than the manufacturing process, while all are important for novel FRs. Correlation analysis between influencing factors and HFRs indicated that the distribution of most pollutants was more affected by anthropogenic source factors than environmental factors. The results of the principal component analysis demonstrated that deca-BDE and its alternative products were the major contributors to the sources of HFRs pollution. Human health risks assessment via oral intake and dermal contact pathways presented that the selected pollutants posed a no-carcinogenic risk to children and adults. It is worth noting that supervision of the disposal process of the NBFRs should be strengthened in the future.

Flame Retardants , Volatile Organic Compounds , Child , China , Environmental Monitoring , Flame Retardants/analysis , Halogenated Diphenyl Ethers/analysis , Humans , Soil
Sci Total Environ ; 803: 150038, 2022 Jan 10.
Article En | MEDLINE | ID: mdl-34525726

Despite several national and local policies towards cleaner air in England, many schools in London breach the WHO-recommended concentrations of air pollutants such as NO2 and PM2.5. This is while, previous studies highlight significant adverse health effects of air pollutants on children's health. In this paper we adopted a Bayesian spatial hierarchical model to investigate factors that affect the odds of schools exceeding the WHO-recommended concentration of NO2 (i.e., 40 µg/m3 annual mean) in Greater London (UK). We considered a host of variables including schools' characteristics as well as their neighbourhoods' attributes from household, socioeconomic, transport-related, land use, built and natural environment characteristics perspectives. The results indicated that transport-related factors including the number of traffic lights and bus stops in the immediate vicinity of schools, and borough-level bus fuel consumption are determinant factors that increase the likelihood of non-compliance with the WHO guideline. In contrast, distance from roads, river transport, and underground stations, vehicle speed (an indicator of traffic congestion), the proportion of borough-level green space, and the area of green space at schools reduce the likelihood of exceeding the WHO recommended concentration of NO2. We repeated our analysis under a hypothetical scenario in which the recommended concentration of NO2 is 35 µg/m3 - instead of 40 µg/m3. Our results underscore the importance of adopting clean fuel technologies on buses, installing green barriers, and reducing motorised traffic around schools in reducing exposure to NO2 concentrations in proximity to schools. Also, our findings highlight the presence of environmental inequalities in the Greater London area. This study would be useful for local authority decision making with the aim of improving air quality for school-aged children in urban settings.

Air Pollutants , Air Pollution , Air Pollutants/analysis , Air Pollution/analysis , Bayes Theorem , Child , Environmental Exposure/analysis , Environmental Monitoring , Humans , London , Nitrogen Dioxide/analysis , Particulate Matter/analysis , Schools , World Health Organization
Sci Total Environ ; 803: 150016, 2022 Jan 10.
Article En | MEDLINE | ID: mdl-34525731

Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) are widely used in outdated electronic and electrical products. In the present study, dust samples from houses, kindergartens, and roads were collected in Guiyu, where informal e-waste recycling activities have been sustained since the 1980s. Haojiang was chosen as a reference site without e-waste pollution. A total of 20 PBDE congeners and 18 PCB congeners was measured. Concentrations of total PBDEs and PCBs in dust samples from Guiyu were significantly higher than those from Haojiang. In Guiyu, kindergarten dust had the highest concentration of PCBs in these three typical environments, whereas the concentration of PBDEs showed no significant difference. Concentrations of PBDEs in Haojiang house dust were found significantly higher than other two environmental dusts. According to the questionnaires, we found that factors such as shoe cabinets, electrical products, and potted plants might affect PBDE and PCB concentrations in house dust. Daily intake of PBDEs and PCBs via dust ingestion was estimated after correction by their house, kindergarten, and road dust concentrations. The mean estimated daily intake (EDI) of PBDEs for Guiyu children was far lower than the oral reference dose recommended by the environmental protection agency (EPA). The Guiyu children seem to have a higher trend of daily intakes of PCBs although their EDIs not being calculated accurately due to the low detection rate. Child exposure to PBDEs via dust ingestion in Guiyu was 36 times higher than those in Haojiang. This indicates that children from e-waste-polluted areas stay in surroundings with heavy burdens of PBDEs, even PCBs. The risk to their health from contaminants is a severe concern.

Electronic Waste , Polychlorinated Biphenyls , Child , Dust/analysis , Electronic Waste/analysis , Environmental Monitoring , Halogenated Diphenyl Ethers/analysis , Humans , Polychlorinated Biphenyls/analysis , Risk Assessment
Sci Total Environ ; 803: 149901, 2022 Jan 10.
Article En | MEDLINE | ID: mdl-34525741

The surface operations area of an underground coal mine near Lingwu in Ningxia Hui Autonomous Region was selected for this study. Particulate matter (PM) was sampled in the coal screening plant during the day and night in Spring and Winter, 2019. Twelve trace metals and eight water-soluble ions in particulate matter up to 10 µm in diameter (PM10) and total suspended particles (TSP) were analyzed using ICP-OES and ion chromatography, respectively. The enrichment factor (EF) and positive matrix fraction (PMF) were used to identify potential sources of particulate metals. The forward trajectory model was used to analyze the main migration pathways of particles. Results showed that higher concentrations of PM10 and TSP were found in Spring than in Winter; the concentration of PM at night was lower than during the day. Most of the trace metals in TSP were greater than in PM10, while the content of most water-soluble ions in TSP was lower than in PM10. The EF analysis confirmed that particulate metals were attributable to anthropogenic emission. PMF model results further demonstrated that the main sources of PM in both seasons were regional suspended dust, traffic emission, industrial emission and coal burning. Air mass dispersion analysis showed that PM generated by these operations may spread to eastern and southeastern China within 72 h in Spring, while mainly to southeastern and southern China in Winter. These suggest a need for greater focus on strengthening the monitoring and early warning of the presence of atmospheric PM in southern Shanxi, China. Because of the risks that particulate metals pose to human health, the protection of children should be strengthened around the surface operation area of an underground coal mine. Moreover, monitoring of the concentrations of Cr in PM10 and Mn in TSP in Spring should be strengthened, and the opposite procedure should be adopted in Winter. These findings are useful for providing a theoretical basis for the prevention and control of pollutants in underground mining areas and the construction of cleaner production lines.

Air Pollutants , Particulate Matter , Air Pollutants/analysis , Child , China , Coal , Environmental Monitoring , Humans , Particle Size , Particulate Matter/analysis , Seasons
Food Chem ; 370: 131062, 2022 Feb 15.
Article En | MEDLINE | ID: mdl-34537431

A simple method was developed to determine 14 endocrine-disrupting chemicals (EDCs) in bottled waters, based on dispersive micro-solid phase extraction (d-µ-SPE) and liquid chromatography-mass spectrometry (LC-MS). Extraction was optimized using 2 k-1 factorial and Doehlert experimental designs. Optimized conditions were 80 mg C18, 25 min extraction at 1000 rpm, and 6 min desorption time. Repeatability was below 17 % for all EDCs. LOD and LOQ varied from 1.60 ng L-1 (estradiol, E2) to 23.2 ng L-1 (dimethylphthalate, DMP) and from 5.33 ng L-1 (E2) to 77.3 ng L-1 (DMP). We found DMP and bisphenol A (BPA) in samples after the heat treatment. DMP was up to 58.7 µg L-1, while BPA was up to 1.34 µg L-1. Tolerance of daily intake (TDI) for DMP were 2.50-2.94 µg kg-1 day-1 (children) and 1.43-1.68 µg kg-1 day-1 (adults). TDI for BPA were 0.03-0.07 µg kg-1 day-1 (children) and 0.01-0.04 µg kg-1 day-1 (adults).

Drinking Water , Endocrine Disruptors , Mineral Waters , Water Pollutants, Chemical , Benzhydryl Compounds/analysis , Child , Endocrine Disruptors/analysis , Humans , Solid Phase Extraction , Tandem Mass Spectrometry , Water Pollutants, Chemical/analysis
Chemosphere ; 286(Pt 3): 131858, 2022 Jan.
Article En | MEDLINE | ID: mdl-34399256

Phthalates and 1,2-Cyclohexane dicarboxylic acid diisononyl ester (DINCH), bisphenols (BPs), parabens (PBs), and triclosan (TCS) are high-production-volume chemicals of pseudo-persistence that are concerning for the environment and human health. This study aims to assess the exposure to 10 phthalates, DINCH, and environmental phenols (3 BPs, 7 PBs, and TCS) of Slovenian men (n = 548) and lactating primiparous women (n = 536). We observed urinary concentrations comparable to studies from other countries and significant differences among the sub-populations. In our study, men had significantly higher levels of phthalates, DINCH, and BPs, whereas the concentrations of PBs in urine were significantly higher in women. The most significant determinant of exposure was the area of residence and the year of sampling (2008-2014) that mirrors trends in the market. Participants from urban or industrialized sampling locations had higher levels of almost all monitored analytes compared to rural locations. In an attempt to assess the risk of the population, hazard quotient (HQ) values were calculated for individual compounds and the chemical mixture. Individual analytes do not seem to pose a risk to the studied population at current exposure levels, whereas the HQ value of the chemical mixture is near the threshold of 1 which would indicate a higher risk. We conclude that greater emphasis on the risk resulting from cumulative exposure to chemical mixtures and additional studies are needed to estimate the exposure of susceptible populations, such as children.

Environmental Pollutants , Phthalic Acids , Child , Dicarboxylic Acids , Environmental Exposure/analysis , Esters , Female , Humans , Lactation , Male , Parabens , Phenols
J Sci Food Agric ; 102(1): 417-424, 2022 Jan 15.
Article En | MEDLINE | ID: mdl-34143904

BACKGROUND: Thiamethoxam is widely used to control pests in Chinese kale, popularly consumed leafy vegetables. The potential risk to the environment and human health has aroused much public concern. Therefore, it is important to investigate the degradation behavior, residue distribution and dietary risk assessment of thiamethoxam in Chinese kale. RESULTS: A sensitive analytical method for determination of thiamethoxam and its metabolite clothianidin residue in Chinese kale was established and validated through a quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique with ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The recoveries were 85.4-101.2% for thiamethoxam and 79.5-108.1% for clothianidin, with the relative standard deviations (RSDs) of 0.9-10.2% and 1.8-6.0%, respectively. For the dissipation kinetics, the data showed that thiamethoxam in Chinese kale was degraded with the half-lives of 4.1 to 4.5 days. In the terminal residue experiments, the residues of thiamethoxam were 0.017-0.357 mg kg-1 after application 2-3 times with a preharvest interval (PHI) of 7 days under the designed dosages. The chronic and acute dietary exposure assessment risk quotient (RQ) values of thiamethoxam in Chinese kale for different Chinese consumers were 0.08-0.19% and 0.05-0.12%, respectively, and those of clothianidin were 0.01-0.04% and 0.02-0.04%, respectively, all of the RQ values were lower than 100%. CONCLUSION: Thiamethoxam in Chinese kale was rapidly degraded following first-order kinetics models. The dietary risk of thiamethoxam and clothianidin through Chinese kale was negligible to consumers. The results from this study are important reference for Chinese governments to developing criteria for the safe and rational use of thiamethoxam, setting maximum residue levels (MRLs), monitoring the quality safety of agricultural products and protecting consumer health. © 2021 Society of Chemical Industry.

Brassica/chemistry , Chromatography, Liquid/methods , Guanidines/metabolism , Neonicotinoids/metabolism , Pesticide Residues/chemistry , Pesticide Residues/metabolism , Tandem Mass Spectrometry/methods , Thiamethoxam/chemistry , Thiamethoxam/metabolism , Thiazoles/metabolism , Adolescent , Adult , Aged , Aged, 80 and over , Brassica/metabolism , Child , Child, Preschool , China , Dietary Exposure/adverse effects , Dietary Exposure/analysis , Female , Food Contamination/analysis , Humans , Kinetics , Male , Middle Aged , Risk Assessment , Vegetables/chemistry , Vegetables/metabolism , Young Adult
Oral Maxillofac Surg Clin North Am ; 34(1): 179-187, 2022 Feb.
Article En | MEDLINE | ID: mdl-34602322

Most jaw lesions are treated surgically. Areas of abnormal proliferation or destruction in bone are commonly treated by regional curettage, excision, or resection. However, surgery is invasive and leaves a defect where the lesion was removed. Surgical trauma to adjacent healthy tissue, including vital neurovascular bundles is often unavoidable, and can be especially traumatizing to the pediatric patient. Select jaw lesions with well-studied nonsurgical pharmaceutical treatments are presented here.

Bisphosphonate-Associated Osteonecrosis of the Jaw , Bone Density Conservation Agents , Child , Diphosphonates , Humans , Medication Therapy Management
Parasitol Int ; 86: 102482, 2022 Feb.
Article En | MEDLINE | ID: mdl-34673233

Dirofilaria spp. nematodes are accidental parasites of humans causing mild to serious, superficial or visceral infections. Superficial dirofilariosis is rather common in Europe and is typically manifested as subcutaneous form. Herein we report 46 new cases of human dirofilariosis (19 patients with subcutaneous, 18 patients with ocular, 4 patients wih genital, 2 patients with submucosal, 2 patients with pulmonary and 1 patient with intramuscular form of infection) that were recorded from the beginning of 2015 to May 2021 on the Balkan Peninsula with a goal to update the prevalence of this parasitosis and point out potential problems in diagnosis and treatment. Besides, given the high possibility of misinterpretation as tumor, our second aim was to encourage the inclusion of this pathogen in the differential diagnosis of subcutaneous nodules. Although quite common forms, subcutaneous and ocular dirofilariosis can be very often misdiagnosed in clinical practice due to the absence of specific clinical manifestations. Therefore, raising awareness of clinicians about this zoonosis is needed as well as closer collaboration between physicians and veterinarians.

Dirofilariasis , Zoonoses , Adolescent , Adult , Aged , Animals , Balkan Peninsula/epidemiology , Child , Child, Preschool , Dirofilariasis/diagnosis , Dirofilariasis/parasitology , Female , Humans , Male , Middle Aged , Prevalence , Serbia , Young Adult , Zoonoses/diagnosis , Zoonoses/epidemiology , Zoonoses/parasitology
Clin Imaging ; 81: 122-135, 2022 Jan.
Article En | MEDLINE | ID: mdl-34710802

Chronic recurrent multifocal osteomyelitis (CRMO) is a distinct disease entity of unknown etiology primarily affecting children and adolescents. It is an autoinflammatory process that typically affects multiple bones with a waxing and waning course. About one third of the patients diagnosed with CRMO have spinal involvement which can lead to long term morbidity. The clinical presentation and imaging features of CRMO involving the spine are nonspecific and can mimic other disease processes like infection or malignancy. Since imaging plays a very important role in the diagnosis and management of CRMO, we intend to highlight various imaging patterns of spinal CRMO alongside its clinical features and briefly discuss its imitators, management and outcomes.

Osteomyelitis , Whole Body Imaging , Adolescent , Child , Chronic Disease , Humans , Magnetic Resonance Imaging , Osteomyelitis/diagnostic imaging , Radiologists , Recurrence
Dermatol Clin ; 40(1): 1-8, 2022 Jan.
Article En | MEDLINE | ID: mdl-34799030

Clinical genetic testing enables the detection of specific gene mutations and variants that predispose individuals and their family members to disease. In recent years, tremendous strides have been made in the variety of clinically useful tests. Targeted testing for specific mutations that cause well-known syndromes enables the efficient diagnosis of genetic diseases with cutaneous manifestations. Testing for specific genes, however, may not always reveal a diagnosis. Expanded options are available. This review outlines the major types of available technology with a focus on those tests most useful for pediatric dermatologists.

Dermatology , Child , Genetic Testing , Humans , Mutation
Dermatol Clin ; 40(1): 109-116, 2022 Jan.
Article En | MEDLINE | ID: mdl-34799032

Pediatric populations are expected to bear most of the climate change impacts, with racial minorities and children living in poorer countries being particularly vulnerable. Given their relevance to cutaneous disease, dermatologists should be aware of these climate-sensitive health impacts and the ways in which they intersect with social factors. Strategies including targeted risk communication, motivational interviewing, and storytelling can help facilitate climate discussions during the patient encounter. In this article the authors summarize common dermatologic health impacts related to environmental exposures and provide sample scripts for climate messaging.

Climate Change , Dermatologists , Child , Humans
Dermatol Clin ; 40(1): 25-36, 2022 Jan.
Article En | MEDLINE | ID: mdl-34799033

Patients are commonly referred to pediatric dermatology for the evaluation of pigmented lesions. For families, pediatricians, and dermatologists alike, malignancy is the main fear. In the past few decades, there has been evolving literature to inform diagnosis and management. This article provides an update on the clinical, histopathologic, and ancillary testing for 3 categories of particularly challenging pigmented lesions: congenital melanocytic nevi, spitzoid neoplasms, and pediatric melanoma.

Dermatology , Melanoma , Nevus, Epithelioid and Spindle Cell , Skin Neoplasms , Child , Diagnosis, Differential , Humans , Melanoma/diagnosis , Nevus, Epithelioid and Spindle Cell/diagnosis , Skin Neoplasms/diagnosis
Dermatol Clin ; 40(1): 37-49, 2022 Jan.
Article En | MEDLINE | ID: mdl-34799034

Melanonychia including melanonychia striata in children poses a diagnostic dilemma. Atypical clinical features often raise the possibility of malignancy, and a nail unit biopsy may be recommended. Commensurate with atypical clinical features, the histopathology may also appear alarming. However, accumulating data illustrate that most cases of melanonychia striata are benign and suggest that an alternate approach is often warranted for pediatric patients. Herein, we review the existing data regarding pediatric melanonychia striata and offer an evidence-based approach to its evaluation and management.

Melanoma , Nail Diseases , Nevus, Pigmented , Skin Neoplasms , Child , Humans , Melanoma/diagnosis , Nail Diseases/diagnosis , Nail Diseases/therapy , Nails , Skin Neoplasms/diagnosis
Dermatol Clin ; 40(1): 51-59, 2022 Jan.
Article En | MEDLINE | ID: mdl-34799035

Melanocytic nevi are congenital or acquired benign melanocytic neoplasms. The reason for the appearance of melanocytic nevi is not precisely known. Melanocytic nevi frequently occur in children, constituting a common reason for consultation in pediatric dermatology clinics. In our experience, many parents and caregivers present doubts and fears based more on popular beliefs than on data with valid scientific evidence. This review answers their frequently asked questions, such as the risk of malignancy, the importance of nevi location, the warning signs of malignant transformation, best prevention strategies, and optimal management, based on the most recent scientific evidence available.

Melanoma , Nevus, Pigmented , Nevus , Skin Neoplasms , Cell Transformation, Neoplastic , Child , Humans
Dermatol Clin ; 40(1): 73-81, 2022 Jan.
Article En | MEDLINE | ID: mdl-34799037

The understanding of melanocytes is fundamental to the study of dermatology. These dendritic cells underly the most feared primary cutaneous malignancy, fuel escalating progress in immunotherapy strategies, and invariably underlie entire socioeconomic constructs consciously or unconsciously based on skin tone. Various ethno-genotypes combine with increasing frequency over time, increasing the diversity of skin types that may present with dermatologic diagnoses. Understanding the biology of a variety of skin tones and ethnic practices congruent with distribution of skin tone is invaluable to any physician who wishes to practice efficient and expert care, especially to pediatric patients of this category.

Dermatology , Neoplasms , Skin Diseases , Child , Ethnic Groups , Humans , Skin , Skin Diseases/therapy , Skin Pigmentation
Dermatol Clin ; 40(1): 83-93, 2022 Jan.
Article En | MEDLINE | ID: mdl-34799038

Many dermatologic conditions common in the pediatric population may have unique presentations in skin of color or occur with greater incidence. This may be due to ethnic origin, socioeconomic factors, or other influences. Awareness of the potential variations in skin of color may enhance prompt diagnosis, appropriate treatment, and/or reassurance as indicated.

Dermatology , Skin Diseases , Child , Ethnic Groups , Humans , Skin , Skin Diseases/epidemiology , Skin Pigmentation
Dermatol Clin ; 40(1): 9-23, 2022 Jan.
Article En | MEDLINE | ID: mdl-34799039

Café au lait macules (CALMs) are a normal and frequent finding in the general population, but multiple CALMs raise the possibility of an underlying neurocutaneous disease like neurofibromatosis type I. Certain features of CALMs like number, size, shape, and distribution are important in identifying children at higher risk of having a neurocutaneous disorder or another genetic disorder. Genetic testing can be especially helpful in establishing a diagnosis in atypical presentations, or when the child is young and other features of the disease aside from CALMs have not manifested.

Cafe-au-Lait Spots , Neurofibromatosis 1 , Cafe-au-Lait Spots/genetics , Child , Genetic Testing , Humans , Neurofibromatosis 1/complications , Neurofibromatosis 1/genetics
Dermatol Clin ; 40(1): 95-102, 2022 Jan.
Article En | MEDLINE | ID: mdl-34799040

Pediatric dermatology is an incredibly rewarding field. Children are resilient and funny and just want to know that you are advocating for their best interests. Teaming up with children and their parents can lead to fantastic therapeutic alliances and success. The author has divided this chapter based on a handful of common pediatric dermatologic diseases and what he sees as some of the main clinical and therapeutic tips and tricks that have helped him in his practice.

Dermatology , Skin Diseases , Child , Humans , Skin Diseases/therapy